Ambitious Apollo 15 Mission Took Lunar Exploration to the Next Level

‘America to the Moon’ Part 13: Exploring the Moon with a ‘Dune Buggy‘

By Bob Granath

During the summer of 1971, 50 years ago, three astronauts made the most of three days on the Moon’s surface and in lunar orbit. With the opportunity for more detailed exploration and the addition of “dune buggy”-like transportation, Apollo 15 was the most complex flight to date.

“It was an exciting mission to go to explore the mountains of the Moon,” said lunar module pilot Jim Irwin in a March 19, 1987 address to employees at NASA’s Kennedy Space Center. “We also had the first ‘car’ on the Moon.”

The battery-powered four-wheeled lunar roving vehicle, or LRV, allowed Irwin and mission commander David Scott to venture out more than 17 miles around their landing site.

When Scott, Irwin and command module pilot Al Worden were assigned as the crew in late 1969, the mission was to be similar to the previous lunar landings. Eight months later, it was changed from nine to a 12-day mission. Instead of one-and-a-half days on the Moon, the mission was extended to three days. With longer periods of exploring, lunar geology training was stepped up in hopes that Scott and Irwin might find rocks and soil samples that could unlock secrets of the origins of the Moon.

Scientists were optimistic because Apollo 15 was headed for a landing site surrounded by the Hadley-Apennine Mountains to the south and east. To the west was Hadley Rille, a steep-walled valley about 0.9 mile-wide and 1,300-feet-deep, winding for more than 60 miles. Experts believed volcanic processes formed the rille and this would provide material from deeper in the lunar crust than was sampled in previous Apollo landing sites.

An All Air Force Crew

A native of San Antonio, Texas, Scott graduated from the U.S. Military Academy at West Point in 1954. While serving in the U.S. Air Force, he earned two advanced degrees from the Massachusetts Institute of Technology in 1962 before being selected as a member of the third group of NASA astronauts the next year. He flew on Gemini 8 in 1966 alongside Neil Armstrong and was command module pilot of Apollo 9 in 1969.

Worden was born in Jackson, Michigan, and attended West Point, receiving a bachelor’s degree in 1955. He also entered the Air Force and later was awarded two master’s degrees in engineering from the University of Michigan in 1963.

Irwin grew up in Pittsburgh and attended the U.S. Naval Academy, graduating in 1951. He joined the Air Force and was awarded a master’s degree from Michigan in 1957. Both Worden and Irwin were members of the fifth group of astronauts selected in 1966 and all three were Air Force test pilots.

While the geology training took place in exotic places such as the California desert and Hawaii, many of the simulations for the Moonwalks occurred in a field near what is now Kennedy’s Neil Armstrong Operations and Checkout Building. The site, known as the “rock pile,” allowed astronauts to practice using their geology tools and learn to drive the lunar rover.

“To develop and practice our geology procedures, tons of volcanic cinders, rocks and boulders were unloaded at a large area behind the training building,” Scott said in the book Two Sides of the Moon that he co-authored in 2004 with Russian cosmonaut Alexei Leonov. “We attempted to make it roughly resemble the lunar surface.”

 ‘I’ll never forget that morning.’

With months of preparation and training complete, Apollo 15 lifted off from Kennedy’s Launch Complex 39A at 9:34 a.m. EDT on a hot, sunny day, July 26, 1971. The Saturn V rocket propelled the astronauts and their spacecraft with 7.5 million pounds of thrust.

“I’ll never forget that morning and the power (of the rocket) that you assembled for us,” Irwin said in his 1987 remarks to people who work at the Florida spaceport.

After the third stage of the Saturn V, called the S-IVB, fired sending the Apollo 15 crew from Earth orbit to a trajectory aimed at the Moon, Scott had high praise for those who supported their successful liftoff.

“As we watch the S-IVB drift away, how about passing along to Jim Harrington (space vehicle test supervisor) at the Cape, congratulations from the crew to the launch team for a superior job,” Scott said. “Smooth all the way and right on time.”

After entering lunar orbit three days after liftoff, Scott and Irwin climbed aboard their lunar module, or LM. The crew named the LM “Falcon” after the mascot at the U.S. Air Force Academy in Colorado Springs. They undocked from the command module, or CM, called Endeavour for British explorer Capt. James Cook’s ship used for his three-year voyage of discovery in the South Pacific.

Four hours after undocking, the lunar module safely landed between mountain ranges and the rille.

“OK, Houston, the Falcon is on the plain at Hadley,” Scott said reporting touchdown to Mission Control at the Manned Spacecraft (now Johnson Space) Center in Houston.

Shortly after landing, he performed Apollo’s only “stand up” extravehicular activity, or EVA, venturing partially outside. Scott opened the Falcon’s top hatch, normally used for docking and transfer back and forth between the CM and LM. He spent about a half-hour checking out the surroundings. He used the time to describe what he saw and plan for the three Moonwalks.

“All of the features around here are very smooth,” he said. “The tops of the mountains are rounded off. There are no sharp, jagged peaks or large boulders apparent anywhere.”

This was what Apollo Mission Director Chet Lee wanted to hear. Before the mission began, he explained that scientists wanted to understand how the mountains and the rille formed as well as their age.

“The material we hope to see is deeper seated crustal material and some of the basaltic lava we have seen before from a different area,” he said.

‘Exploration at its greatest.’

On July 30, 1971, Scott climbed down Falcon’s ladder and stepped on to the surface.

“As I stand out here in the wonders of the unknown at Hadley, I sort of realize there’s a fundamental truth to our nature,” he said. “Man must explore and this is exploration at its greatest.”

Among Scott and Irwin’s first tasks was unfolding the lunar rover stored on the side of the LM. On the right front fender of the rover was a television camera that could be controlled remotely from Mission Control by NASA’s Ed Fendell. The resolution was improved compared to the color cameras on Apollos 12 and 14. The images also helped geologists on Earth to observe and assist with Scott and Irwin’s activities.

The astronauts drove to a nearby crater, collected rock and soil samples and went back to their landing site. They set up their Apollo Lunar Surface Experiments Package, or ALSEP, a collection of scientific instruments that would continue to send data back well after they returned to Earth.

As Scott and Irwin drove around during their second day of geology exploration, they spotted something unusual.

“We drove up the side of a mountain about a thousand feet,” Irwin said. “We saw a rock sitting on another almost free of dust. It seemed to be saying, ‘I’m here, take me!’”

Upon seeing the rock at the time, Scott knew the geology training had paid off.

“Guess what we just found,” he radioed back to Mission Control. “I think we found what we came for.”

It was a white anorthosite weighing about half a pound. Geologists later dubbed it the “Genesis Rock” as it turned out to be over four billion years old. It is a piece of ancient lunar crust that has since been extensively studied.

“God guided us to the discovery of the white rock,” Irwin said later. “It has helped scientists better understand the early history of the Moon and the early history of Earth.”

‘I will lift up my eyes unto the hills.’

While riding in the rover to return to the lunar module on the third day of their stay on the Moon, Scott commented on their surroundings.

“Oh, look at the mountains today, Jim. When they’re sunlit, isn’t it beautiful?” he said.

“It really is,” Irwin answered.

“Dave, I’m reminded of a favorite Biblical passage in Psalms: ‘I will lift up my eyes unto the hills, from whence cometh my help,’” Irwin said, quoting Psalm 121:1 in the Bible.

“By golly, that’s just super!” Scott said. “Oh, it’s — you know, unreal.”

After nearly three days on the surface at the Hadley-Apennine landing site, Falcon launched from the Moon on Aug. 2, 1971, to rendezvous with Worden in lunar orbit. With the TV camera mounted on the rover, those in Mission Control and viewers at home saw — for the first time — the LM’s accent module lifting off from the Moon.

While his crewmates explored the Moon from the surface, Worden remained in lunar orbit, operating sensors in a scientific instrument module mounted in the spacecraft’s exterior. While circling the Moon for 74 times, he deployed a small sub-satellite that was left in lunar orbit.

During the return flight home, Worden became the first to perform a spacewalk outside of Earth orbit. With Irwin assisting in the command module hatch, Worden retrieved film canisters from the scientific instrument module bay in the service module during 38 minutes outside.

After splashdown in the North Pacific Ocean on Aug. 7, 1971, the crew was picked up and taken aboard the recovery ship, the USS Okinawa. The mission lasted 12 days, seven hours.

NASA Administrator James Fletcher praised the entire NASA team following the mission.

“I must say that I have been impressed with the dedication and hard work of all of you,” he said.

And, according to the initial report of NASA’s Apollo Geology Investigation Team, Scott, Worden and Irwin’s request for enhanced geology training paid off.

“The objectives were optimistic, ambitious and largely due to the outstanding competence of the Apollo 15 crew (requesting additional geology training),” the report said. “Collectively, their achievements promise an extraordinarily scientific yield for the Apollo 15 mission.”

Apollo 15 and all the lunar missions helped pave the way for efforts years into the future. What was learned from these missions, NASA now is using to help plan to land the first woman and the first person of color on the Moon as part of the agency’s Artemis lunar exploration program. The project is designed as a collaboration with contractors, commercial and international partners to explore more of the lunar surface than ever before. What is learned on and around the Moon will later be used to send astronauts to Mars.

© 2021 SpaceAgeChronicle.com All Rights Reserved

High Flight

By Bob Granath

After the Apollo 15 flight to the Moon, Jim Irwin began receiving requests to speak to civic groups and churches. In his presentations, he explained that walking on the lunar surface and looking up at his home planet transformed his outlook.

“My life changed because I saw the Earth from that faraway place and realized how unique the Earth is, how special it is,” he said. “It was a beautiful, blue jewel in the blackness of space. I felt strangely at home on the Moon. The days I spent on the Moon were very exciting. Not because I was there, but because God was there. I could feel His presence.”

According to Irwin’s minister and friend, Rev. Bill Rittenhouse, then pastor of Nassau Bay Baptist Church in Houston, the astronaut sensed a calling to share his experiences.

“He felt the awesome presence of God and experienced firsthand evidence that showed how intricately God cares for us,” Rittenhouse said in his 1976 book, Barbed Wire Preacher. “Because of the extraordinary life-changing event, he came away from the Moon flight with a profound sense of responsibility to all mankind.”

To share his experiences, Irwin, together with Rittenhouse, formed the High Flight Foundation in July 1972. Through the organization, Irwin and his family worked to encourage others.

“As a result of my flight to the Moon, I’ve had a chance to travel around the world and visit many places to share the adventure of my flight into space,” Irwin said in a March 19, 1987 address to employees at NASA’s Kennedy Space Center. “Now I know my ‘flight’ through life has been sustained by the power of my knowledge of Jesus Christ. I’ve been sharing the story of adventure, the story of exploration and the story of His truth.”

Over a period of nearly 20 years, Irwin suffered a series of heart attacks. Following a fourth, he died Aug. 8, 1991 at the age of 61 and was buried at Arlington National Cemetery.

Irwin’s wife, Mary Ellen, and their five children carry on the work of the High Flight Foundation as “Goodwill Ambassadors working hand in hand with leaders serving the nation and the people as they discover God’s destiny for their lives.”

Click here to learn more about the High Flight Foundation.

EDITOR’S NOTE: This is the 13th in a series of feature articles marking the 50th anniversary of NASA’s Apollo missions to the Moon. During the 1960s and early 1970s, the space agency and its contractors sent astronauts from Earth beginning a period of exploration that will lead to pioneering flights planned for the 21st century. Next April, read about exploring the Moon’s Descartes Highlands.

© 2021 SpaceAgeChronicle.com All Rights Reserved